Transmission filter question

[sweetwater]

I just sucked out the fluid from my ZF tranny...read full but only about a quart and a half came out. I sucked it out of the hole in the filter basin. So...my questions.. How should the level be read? I have heard you should read the dipstick by just placing it in the hole and not screwing it in?? And also how the heck do you re-install the round filter cover? I placed the filter back in the hole, put on the o-ring and cover and threaded in the cover bolt. However, it appears the bolt threads into the flter itself which would compress the o-ring but not provide an actual mechanical connection holding down the cover. Am I missing something? Thanks again!

[Pitou]

Glad to hear that you are servicing your gear. I do this as an annual service as recommended by ZF. I've had mechanics tell me it is overkill, but in my mind it is inexpensive PM especially if your doing it yourself. I do the same with the engine coolant as well.

You are reading the dipstick correctly by not screwing it in & resting it on top of the threads. The fluid should be in-between the 2 level marks. The capacity of your gear .... I'd think more than 1.5 quarts, mine holds 6. I service my gear the same way by sucking the fluid out by sticking a "thin" dipstick tube down through the center of the filter sump to the bottom of the gear and am able to get 5.5 qts. of the ATF fluid removed. Which gear do you have? I have the ZF booklet which lists capacities for most gears and would be happy to look it up. When you refill be sure to run the engine & engage the gear forward & reverse to get the fluid to flow throughout the gear, lines and cooler then shutdown and wait 5 minutes to read the dipstick and top off as necessary.

As far as replacing the cover you are correct that there is not a mechanical connection securing the cover and that as you tighten the bolt, 6mm I believe, the "o"ring expands and that is it. Be sure to apply pressure downward on the cover before final tightening of the bolt to ensure the cover is down, level and secure. The tab on the cover will come up upon the housing and allow the final tightening and resulting expansion of the "o"ring to hold the cover secure. No need to overtighten as there is no back pressure on the cover and you want to be able to remove it next year.

[RobS]

Nicely done Kev. In the 28TE the 6LP is mated with a model 63 zf tranny which will hold btwn 4 and 4.5 qts

[sweetwater]

Thanks guys, I figured out that the tube I used was not long enough to get to the bottom of the sump, used a thinner one and got about 4.5 quarts. As for this cover, the tab seems to rest about 1/16 off the tranny and the top of the cover is not flush....sound right? I placed the filter in, put the o ring on top, put the cover with the washer on it and tightened the whole thing up. not sure how this tab comes into play or how it should rest when done.

[RobS]

No, it should be a contact fit as in this picture.
You can also see where the tab hits the case.
Did you go with the OEM filter, part #3312199031?
Attached is a spec sheet on the tranny that also shows the filter cover in place.

[OldDemps]

What's the best source for buying the filters?
How much are they?

THANKS

[RobS]

I get mine from a local marine gear shop. They are just north of $50.. Google the part number I posted and you can likely find an online source.

[sweetwater]

Robs, Thanks for the picture. It looks like the cover in that picture is a little higher than the case.. the bottom of the cover sits into the case but the top of the cover... and the bottom of the tab are a bit higher than the case. Am I right. Sorry about all the questions.. dont want to mess it up.

[RobS]

I was down at the boat when your post notification email came through so I took a couple close-up pictures for you. Click on the images to enlarge. This should clear it up..

(Hey Doug, nice photos for a cellphone, I don't think you could squeeze an iPad down there like I could my droid! )

[sweetwater]

WOW, What service!! Thanks so much... Thats how mine looks now. I hope I can return the favor for you... Thanks again.